A driving force transmitting device, that transmits a rotational driving force from a driving force generating device by means of engagement of a plurality of gears, has been conventionally known. In such a driving force transmitting device, a reducing gear such as a two stage gear is used in order to amplify a driving force from a driving force generating device. In such a driving force transmitting device, generally: (1) as shown in Patent Document 1 below, a second gear that receives a rotational driving force transmitted from a first gear on a downstream side of the first gear (two stage gear) is in a state of being engaged with a small wheel that rotates concentrically with a rotational shaft within a root circle of the first gear. A position where a rotational shaft of the second gear is disposed is configured to be outside of a large wheel of the first gear, in order that the second gear is pivotally supported by a device main body of the driving force transmitting device. (2) Alternatively, in a case in which the rotational shaft of the second gear is disposed at a position within the root circle of the first gear, the pivotal support of the second gear in the driving force transmitting device is realized by providing a separate bearing member for pivotally supporting the rotational shaft of the second gear at the position where the rotational shaft of the second gear is disposed.
Patent Document 1: Japanese Unexamined Patent Application Publication No. 2008-75872